Solid State Drive (SSD)

Solid State Drive

Definition

A solid state drive (also known as SSD) is an electronic storage drive built on solid state architecture. SSDs are built with NAND and NOR flash memory to store non-volatile data and dynamic random access memory (DRAM). A SSD and magnetic hard disk drive (HDD) share a similar purpose.

Unlike a hard drive, an SSD has no moving parts which gives it advantages such as faster access time, noiseless operation, higher reliability, and lower power consumption.

As the costs have come down, SSDs have become suitable replacements for a standard hard drive in both desktop and laptop computers. SSDs are also a great solution for netbooks, laptops, and other applications that don't require a lot of storage.

SSD incorporates the storage technique implemented in microchip-based flash memory, where data is electronically stored on flash memory chips. An SSD is an entirely electronic storage device, and its physical assembly contains no mechanical objects. A spinning HDD reads and writes data magnetically, which is one of the oldest storage media in continuous use. The magnetic properties, however, can lead to mechanical breakdowns. An SSD, conversely, reads and writes the data to a substrate of interconnected flash memory chips, which are fabricated out of silicon. Manufacturers build SSDs by stacking chips in a grid to achieve varying densities.

To prevent volatility, SSD manufacturers design the devices with floating gate transistors (FGRs) to hold the electrical charge. This allows an SSD to retain stored data even when it is not connected to a power source. Each FGR contains a single bit of data, designated either as a 1 for a charged cell or a 0 if the cell has no electrical charge

Components

A SSD has two key components:

• Flash memory: Contains storage memory.
• Controller: An embedded microprocessor that processes functions, like error correction, data retrieval and encryption. Manages access to input/output (I/O) and read/write (R/W) operations between the SSD and host computer.

Type of SSD

SSDs also come in different form factors. This refers to the physical size, shape and connector of the SSD:

2.5 Inch SSD

→ 2.5-inch - The most common type. They’re the same physical size and shape as a mechanical hard drive and fit into the same space as mechanical hard drives.

M.2 SSD

→ M.2 - M.2 SSDs are thin memory sticks and fit onto the motherboard via an M.2 slot or M.2 connector. Some M.2 slots can only take SATA SSDs, while others can take both SATA SSD and PCIe-NVMe SSD.

Add-in Card SSD

→ Add-in card (AIC): These are only seen on desktops. They plug into a motherboard's PCIe x4 or x16 slot, which are most typically used for GPUs or RAID controllers. Partially thanks to their large surface area, AIC SSDs, such as the Intel Optane 900p, are among the fastest SSDs.

U.2 SSD

→ U.2: These look like SATA SSDs but use a different connector and speed data via the speedy PCIe interface. They also tend to be pricier and have larger capacity than M.2 SSDs.